Veneers failure generally takes place from separation of bonded borders, intracomposite crack, or crack of at the bottom of tooth structure.  Force strength, time, occurrence and direction verses restitution power decide success or failure of a restoration. 

Elimination of caries and earlier placed restitutions, tooth breakage, or enhancing tooth dimensions, tooth areas where no backing takes places. A translucent restoration will show during dark from the back of the mouth and emerge darker. Composite should block out dark from the back of the mouth.  Placement of opaque material or dentin shades covered with translucent material produces a natural looking restoration that is not influenced by this darkness.   Amalgamation composite veneers color to tooth color is gained further by appropriate composite selection, placement and design preparation.

Caries, faulty restorations and feeble tooth structure are aloof.  Diamond burs shape remaining tooth structure to accept composite by leaving a rough surface for improved bond strengths.

Enamel and dentin bonding gives strength to grasp complex onto tooth structure, reduce microleakage and warmth.  Elimination of caries has attention of the mechanical skills.  Strength of enamel bonding is boosted through beveling around the enamel rods.  A long enamel bevel makes more surface area for strength and gives a long steady show in the course of tooth structure for enhanced and natural color transition.  A translucent outer layer of composite gives a chameleon result picking up and viewing around surrounding color.

Enamel and dentin bonding is performed to exploit interface strength. Acid is putted on enamel up to 15-30 seconds. Acidity is defused so only 10 microns of enamel is aloof.